Publication details.

Paper

Year:2018
Author(s):A. Payo-Payo, A. Sanz-Aguilar, D. Gaglio, R. Sherley, T. Cook, R. Altwegg, P. Ryan
Title:Survival estimates for the greater crested tern Thalasseus bergii in southern Africa
Journal:AFRICAN JOURNAL OF MARINE SCIENCE
ISSN:1814-232X
Volume:40
Issue No.:1
Pages:43-50
D.O.I.:10.2989/1814232X.2018.1437470
Web:https://dx.doi.org/10.2989/1814232X.2018.1437470
Abstract:© 2018 NISC (Pty) Ltd. The nominate race of the greater crested tern Thalasseus bergii breeds only along the coast of the Benguela region (west coast) of southern Africa, where its population is increasing, in contrast to other species of breeding seabirds in the region which similarly depend on forage fish. Although this population’s trends are well known, its demographic parameters remain obscure. We used multi-event capture–recapture–recovery modelling to provide the first estimates of survival. The survival rate of birds older than two years was 0.93 (0.91–0.95); second-year survival was 0.93 (0.90–0.95) and first-year survival was 0.80 (0.73–0.85). A resighting of a 34-year-old bird is a new longevity record for the species. Population growth rates projected with a Leslie matrix model that included our survival estimates were very similar to estimates from annual counts of the breeding population (7–8% y−1), suggesting that these survival estimates adequately describe the species’ demography. High survival rates have likely contributed to the species’ recent population increase in the region.

Related staff

  • Ana Sanz Aguilar
  • Related departments

  • Animal and Microbial Biodiversity
  • Related research groups

  • Ecology and Evolution